The 250-megawatt project, to be built and managed by a subsidiary of Florida-based NextEra Energy Resources, got a unanimous go-ahead from state energy regulators. Beacon first applied for approval in 2008.

Sprawling across 2,012 private acres in Kern County, the installation will use parabolic trough solar thermal technology. Long rows of curved mirrors will collect energy from the sun, heating tubes filled with fluid to help run a steam turbine generator.

The Energy Commission last approved a solar thermal project in February 1990, when it allowed a plant in San Bernardino County to move forward. But smaller arrays, which don’t require a license through the commission, have popped up along the way.

Before the Beacon project breaks ground, however, it will likely have to secure a power purchase agreement with a utility. California’s investor-owned utilities will likely fail to reach a statewide mandate to get at least 20% of their electricity from renewable sources by the end of 2010.